1. Field of the Invention
This invention relates to detergent compositions and in particular to alkali containing detergent compositions containing nonionic surface active agents which have a tendency to discolor the compositions in the presence of such alkali.
2. Description of the Prior Art
Compositions intended primarily for laundering heavily soiled fabrics generally contain two essential compounds: a builder and a surface active agent. Widely used builder materials include alkali materials such as alkali metal hydroxides, alkali metal silicates and the like. Due to the increasing concern for the conservation of energy, there have been developed certain highly alkaline detergent compositions which perform satisfactorily, particularly in commercial laundering operations, at low washing solution temperatures, i.e., less than about 140.degree. F. (60.degree. C.). A particularly preferred composition is described in U.S. Application Ser. No. 911,589 to Cristobal, Newsbaum and Baylog, filed on May 31, 1978, the entire disclosure of which is incorporated herein by reference. A problem associated with these highly alkaline detergent compositions is that the nonionic surface active agents employed therein tend to discolor the compositions in the presence of such high alkalinity and impart, for example, a dark brown color to the detergent composition upon aging at room temperature and/or elevated temperatures. This is highly undesirable for the commercial sale of the product.